No one on this website could give you careful advice without knowing much more information. One option would be to consult with the National Labor Relations Board. Oklahoma is the NLRB's Region 14 and the NLRB has a small office in Tulsa. They may be able to consult with you over the phone. Contact information is below.
224 South Boulder Avenue, Room 318
Tulsa, OK 74103-3027.
Phone: (918) 581-7951
My answers to questions posted on AVVO are intended to provide general information only, and are not intended to be legal advice. Employment law issues typically require a careful case-by-case analysis. Consequently, if you feel that you need legal advice, I would encourage you to consult in person with an employment attorney in your area.
The relationship between a company and a union is often one born of compromise after negotiation..
If something has occurred that would qualify as being corrupt action, it seems rather unlikely the fault would rest exclusively on the company with the union being an unfortunate and unwilling victim.